Manufacture of incandescing electric lamps



(No Model.)

T. A. EDISON.

MANUFACTURE OF INGANDESGING ELECTRIC LAMPS. No. 264,650. Patented Sept.19, 1882.

fles; 151116715027 UNITED STATES ATENT OFFICE.

THOMAS A. EDISON, OF MENLO PARK, NEW-JERSEY.

MANUFACTURE OF INCANDESCING ELECTRIC LAMPS.

SPECIFICATION formingpart of Letters Patent No. 264,650, dated September19, 1882.

Application filed December 9, 1881. Renewed August 14, 1882.

To all whom "it may concern Be it known that I, THoMAs A. EDIsoN, ofMenlo Park, in the county of Middlesex and State of New Jersey, haveinvented a new and useful Improvement in the Manufacture of Incandescing Electric Lamps (Case No. 382 5) and I do hereby declare that thefollowingis a full and exact description of the same, reference beinghad to the accompanying drawings, and to the letters of reference markedthereon.

The object of this invention is to facilitate the exhaustion of thevacuum-chambers of incandescent electric lamps.

The invention consists in inclosing the lamp while it is being exhaustedin a metallic or other inclosin g case or envelope capable of retainingheat, which envelope will be heated by the current passing through thecarbon of the lamp, and so heat the air remaining in the globe as toassist in driving it out.

- A form of my invention is shown in the drawings, in which Figure l isa view of a lamp surrounded by its metal case; Fig. 2, a detail view ofa portion of the same, and Figs. 3 and 4 views showing the manner offorming another kind of metal case.

0 is the inclosing-globe of an incandescent electric lamp in the processof exhaustion, 8 being its carbon filament and n the exhausttube leadingto the Sprengel air-pump.

D Ris a metal case placed around the lamp, consistingoftwo cones, theupper fitting within the lower, and the whole held against the lamp byspring-fingers d cl. This case may instead be made by punching out apiece of sheet metal, as in Fig. 3, and then bending it up around (Nomodel.)

the lamp-globe, as in Fig. 4. Apertures a, are provided through which toobserve the carbon filament. The current is applied to the carbon 8through the conductors f g, and the heat thus produced heats theinclosingcase D, so that all parts of the globe G are equally heated andthe air is more rapidly driven out.

It is evident that, instead of using the metal case shown, the globemight be coated with a metallic foil or with an opaque powder-such aslam p-black-which can be removed after the lamp has been heated,exhausted, and sealed off.

What I claim is- 1. The combination; with the inclosing-globe of anincandescent electric lamp, of means situated without the globe forretaining the heat caused by the incandescence of the carbon filament,substantially as and for the purpose set forth.

2. The combination, with theinclosing-globe of an incandescent electriclamp, of an inolosing case or envelope adapted to be heated v by theincandescence of the carbon filament and to retain theheat so generated,substantially as and for the purpose set forth.

3. The metal case or envelope composed of radial strips bent up aroundthe globe, substantially as set forth.

This specification signed and witnessed this 5th day of December, 1881.a

T. A. EDISON. Witnesses:

H. W. SEELY, WM. H. MEADowoRoFtr.

